7th Grade Math

Expressions

PART A BCD

Multi-Part

Lesson 1

Get ConnectED

GLE 0706.2.2

Understand and work with

the properties of and

operations on the system of

rational numbers. GLE 0706.3.1

Recognize and generate

equivalent forms for simple

algebraic expressions. Also

addresses SPI 0706.2.1,

SPI 0706.2.3.

Properties

MUSEUMS The admission costs are shown. Science Center Admission

Admission $12

Movie $8

1. Find the total cost of admission and a
   movie ticket for a 4-person family.


2. Explain how you solved.

Here are two ways to find the total cost.

number of people

4 ($12 + $8 )

1 admission and 1 movie

cost of 4 movies

4 ($12 ) + 4 ($8 )

cost of 4 admissions

The expressions 4($12) + 4 ($8) and 4($12 + $8) are equivalent

expressions because they have the same value, $80. This shows how

the Distributive Property combines addition and multiplication.

Distributive Property

Words To multiply a sum by a number, multiply each addend of

the sum by the number outside the parentheses.

Examples Numbers Algebra

3 ( 4 + 6 ) = 3 ( 4 ) + 3 ( 6 ) a(b + c) = a(b) + a(c)

5 ( 7 ) + 5 ( 3 ) = 5 ( 7 + 3 ) a(b) + a(c) = a(b + c)

Use the Distributive Property

Use the Distributive Property to rewrite each expression.

Then evaluate it.

5 ( 3 + 2 ) 3 ( 7 ) + 3(4)

5 ( 3 + 2 ) = 5 ( 3 ) + 5 ( 2 ) 3 ( 7 ) + 3 ( 4 ) = 3 ( 7 + 4 )

= 15 + 10 Multiply. = 3(11) Add.

= 25 Add. = 33 Multiply.

a. 6 ( 1 + 4 ) b. 6 ( 9 ) + 6(3)

Main Idea

Use Commutative,

Associative, Identity,

and Distributive

properties to solve

problems.

Vocabulary

equivalent expressions

properties

38 Expressions and Patterns

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